JP6442435B2 - Polarizing plate and liquid crystal display device - Google Patents

Description

  The present invention relates to a polarizing plate and a liquid crystal display device.

  In recent years, liquid crystal panels for liquid crystal displays are required to be thin. Polarizers used in liquid crystal panels are generally brittle and easy to tear. Therefore, in order to protect them, a protective film is bonded to both sides of the polarizer to form a polarizing plate (see, for example, Patent Document 1), and this is a liquid crystal cell. Adhere to.

Japanese Patent No. 5743291

  Due to demands for further thinning of liquid crystal panels, development of polarizing plates in which a protective film is bonded only to one side of a polarizer has been carried out. However, a polarizing plate in which a protective film is bonded only on one side of the polarizer tends to crack the polarizer during a durability test.

  Therefore, an object of the present invention is to provide a polarizing plate having a protective film only on one side of a polarizer, which is less prone to crack during a durability test. Moreover, it aims at providing a liquid crystal display device provided with the said polarizing plate.

  The present invention is a polarizing plate comprising a polarizer and a protective film laminated only on one side of the polarizer via an adhesive, the protective film being formed into a predetermined shape, The polarizing plate is laminated on the entire surface of one side of the polarizer, and at least a part of the end of the polarizer is located inside the end of the protective film.

  In this polarizing plate, since the edge part of a polarizer is located inside the edge part of a protective film, the edge part of a polarizer is physically protected. Therefore, when the side surface of the polarizing plate receives an impact during the handling of the polarizing plate, it is possible to prevent the end of the polarizer from being scratched or cracked. In addition, cracks are difficult to enter during the durability test.

  In this polarizing plate, all the end portions of the polarizer may be located inside the end portions of the protective film. In this case, all ends of the polarizer are protected.

  This polarizing plate is laminated on at least one of the surface of the polarizer opposite to the side where the protective film is laminated and the surface of the protective film opposite to the side where the polarizer is laminated. A pressure-sensitive adhesive layer may be further provided, and an optical functional film laminated via the pressure-sensitive adhesive layer may be further provided. An example of the optical functional film is a reflective polarizer.

  Moreover, this invention provides a liquid crystal display device provided with the said polarizing plate. Even when a liquid crystal display device in which the polarizing plate is attached to a liquid crystal cell or the like is configured, the end of the polarizer is physically protected.

  ADVANTAGE OF THE INVENTION According to this invention, it is a polarizing plate provided with a protective film only on the single side | surface of a polarizer, Comprising: It can provide the polarizing plate which a crack does not easily enter at the time of an endurance test. In addition, a liquid crystal display device including the polarizing plate can be provided.

It is a perspective view of the polarizing plate of the 1st Embodiment of this invention. (A) is IIa-IIa sectional drawing of FIG. (B) is IIb-IIb sectional drawing of FIG. It is sectional drawing of the polarizing plate of the 2nd Embodiment of this invention. It is sectional drawing of the polarizing plate of other embodiment of this invention. It is sectional drawing of a liquid crystal display device.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments of the invention will be described in detail with reference to the drawings. In addition, in each figure, the same code | symbol is attached | subjected to the same part or an equivalent part, and the overlapping description is abbreviate | omitted. In addition, the dimensional ratios in the drawings do not necessarily match the actual ones, and in particular, the thickness of the film is exaggerated.

<First Embodiment>
As shown in FIGS. 1 and 2, in the polarizing plate 1 </ b> A of the present embodiment, a protective film 3 is laminated on one side of a polarizing film (polarizer) 2 formed in a thin film via an adhesive layer 4. Made up of. The polarizing film 2 and the protective film 3 are formed in a rectangular shape in plan view, and this shape is also the appearance shape of the polarizing plate 1A.

  The polarizing plate 1A is bonded to one side or both sides of a display cell (image display element) such as a liquid crystal cell. It is preferable that the polarizing plate 1 is bonded to the back side of the display cell. The polarizing plate on the back side is more likely to cause dew condensation or the like than the polarizing plate on the viewing side, and the polarizing film is prone to cracks. According to the polarizing plate 1 of this embodiment, the polarizing film 2 is remarkably suppressed from cracking. can do.

  The end portion 2a of the polarizing film 2 is located so as to be recessed inside the end portion 3a of the protective film 3 (center side of the main surface of the polarizing plate 1) over the entire circumference. That is, in the cross-sectional view shown in FIG. 2, the side surface of the polarizing plate 1 </ b> A has a shape in which the side surface of the polarizing film 2 is recessed with respect to the side surface of the protective film 3.

  Here, “the end 2 a of the polarizing film 2” refers to a side that is far from the protective film 3 and that is perpendicular to the thickness direction of the polarizing plate 1 among the sides that constitute the end surface of the polarizing film 2. In addition, “the end portion 3 a of the protective film 3” refers to a side that is far from the polarizing film 2 and that is perpendicular to the thickness direction of the polarizing plate 1 among the sides that constitute the end surface of the protective film 3.

  It is preferable that the edge part 2a of the polarizing film 2 is located inside 1-500 micrometers from the edge part 3a of the protective film 3, It is more preferable to be located inside 2-300 micrometers, It is 5-50 micrometers inside. More preferably, it is located. Especially, it is preferable that it is located inside by the same length over the perimeter of the polarizing film 2 like this embodiment. When the end 2a of the polarizing film 2 is located within these ranges, the effect of physically protecting the end 2a of the polarizing film 2 is particularly high, and a wide display surface is ensured even when a liquid crystal display device is configured. can do.

  The polarizing film 2 and the protective film 3 are bonded and laminated via the adhesive layer 4.

  As the material of the polarizing film 2, known materials that have been conventionally used for the production of polarizing plates can be used. For example, polyvinyl alcohol resin, polyvinyl acetate resin, ethylene / vinyl acetate (EVA) resin, polyamide Examples thereof include resins and polyester resins. Of these, polyvinyl alcohol resins are preferred. When forming into a film shape for bonding with the protective film 3, it is preferable that the uniaxially stretched film is dyed with iodine or a dichroic dye and then treated with boric acid. As will be described later, the film-like polarizer can be cut into an arbitrary size and used at the time of producing the polarizing plate.

  The thickness of the polarizing film 2 is preferably 2 to 30 μm, more preferably 2 to 15 μm, and still more preferably 2 to 10 μm. Generally, the thinner the polarizing film, the easier it is to crack. However, in this embodiment, even if the polarizing film 2 is 10 μm or less, cracks can be remarkably prevented.

  The protective film 3 is a film that prevents the main surface and end of the polarizing film 2 from cracking and scratching. Here, the “protective film” refers to a film physically laminated at a position closest to the polarizing film 2 among various films that can be laminated on the polarizing film 2.

  The protective film 3 can be composed of various transparent resin films known in the field of polarizing plates. For example, cellulose resin whose typical example is triacetyl cellulose, polyolefin resin whose typical example is polypropylene resin, cyclic olefin resin whose typical example is norbornene resin, acrylic whose typical example is polymethyl methacrylate resin Examples thereof include polyester resins and polyester resins having polyethylene terephthalate resins as representative examples. Among these, cellulose resin is representative.

  The thickness of the protective film 3 is preferably 5 to 90 μm, more preferably 5 to 80 μm, and still more preferably 5 to 50 μm.

  As an adhesive which comprises the adhesive bond layer 4, the various adhesives conventionally used for manufacture of a polarizing plate can be used. For example, an epoxy resin that does not contain an aromatic ring in the molecule is preferable from the viewpoint of weather resistance, refractive index, cationic polymerizability, and the like. Moreover, what hardens | cures by irradiation of an active energy ray (an ultraviolet ray or a heat ray) is preferable, and a cationic ultraviolet curable adhesive and a radical type ultraviolet curable adhesive are especially preferable.

  As an epoxy resin, a hydrogenated epoxy resin, an alicyclic epoxy resin, an aliphatic epoxy resin, etc. are preferable, for example. For epoxy resins, polymerization initiators (for example, photocationic polymerization initiators for polymerization by UV irradiation, thermal cationic polymerization initiators for polymerization by heat ray irradiation), and other additives (sensitizers, etc.) Can be added to prepare an epoxy resin composition for coating.

  The resin constituting the radical ultraviolet curable adhesive contains a (meth) acrylic compound having one or more (meth) acryloyloxy groups in the molecule, and an active energy ray (in the presence of a polymerization initiator ( Examples thereof include (meth) acrylic compounds that can be polymerized by irradiation with ultraviolet rays, visible light, electron beams, X-rays, and the like.

  Moreover, as an adhesive agent, the composition containing acrylic resins, such as acrylamide, acrylate, urethane acrylate, an epoxy acrylate, and the water-system adhesive agent containing a polyvinyl alcohol-type resin can also be used.

  The thickness of the polarizing plate 1A composed of the polarizing film 2, the adhesive layer 4, and the protective film 3 is preferably 7 to 120 μm, more preferably 10 to 70 μm, and more preferably 10 to 55 μm. More preferably.

  The polarizing plate 1A can be manufactured, for example, as follows. First, the protective film 3 is cut out into a rectangle from a long film roll made of a material constituting the protective film 3. The size and aspect ratio of the rectangle to be cut out are determined according to the application target of the polarizing plate 1A. An adhesive is applied to one side of the protective film 3. The region where the adhesive is applied is not the entire surface of the protective film 3 but the region where the polarizing film 2 is laminated.

  Next, the polarizing film 2 is cut out into a rectangle from a long film roll made of a material constituting the polarizing film 2. The size of the rectangle to be cut out is smaller than the size of the protective film 3. As an amount to be reduced, the end 2a of the polarizing film 2 is to be recessed inwardly of the end 3a of the protective film 3. The cut-out film-like polarizing film 2 is laminated | stacked on the surface of the protective film 3 which apply | coated the adhesive using a bonding roll, for example. Lamination | stacking here is performed so that the whole surface of the single side | surface of the polarizing film 2 may enter inside the surface of the protective film 3. FIG. Here, when viewed from the protective film 3 side, the polarizing film 2 is covered with the protective film 3. When an active energy ray-curable resin is used as the adhesive, the adhesive is cured by irradiating active energy rays here.

  The polarizing plate 1A is manufactured by the above procedure.

  In the polarizing plate 1 </ b> A described above, the end 2 a of the polarizing film 2 is physically protected because the end 2 a of the polarizing film 2 is positioned inside the end 3 a of the protective film 3. Accordingly, in handling such as when the polarizing plate 1A is attached to a liquid crystal cell, for example, when the side surface of the polarizing plate 1A receives an impact, only the end portion 3a of the protective film 3 receives the impact, and the polarizing film 2 Scratches and cracks are prevented from occurring at the ends of the. This effect is also exhibited in further handling after the polarizing plate 1A is attached to a liquid crystal cell or the like. In addition, the polarizing plate 1A is less likely to crack the polarizing film 2 in a durability test such as a heat shock test.

  Moreover, since the end 2a of the polarizing film 2 is protected by the end 3a of the protective film 3, the effect of the polarizing plate 1A is excellent particularly in the recent trend toward narrowing the frame of the liquid crystal cell. That is, when the frame of the liquid crystal cell to which the polarizing plate 1A is attached has a normal width, the liquid crystal cell itself has a function of protecting the polarizing film 2 from physical shock, but the liquid crystal cell has a narrow frame. If it exists, the effect of the protection becomes small. In this case, the ratio that the end 3a of the protective film 3 on the liquid crystal cell side contributes to the protection of the end 2a of the polarizing film 2 is increased.

  Since the end 2a of the polarizing film 2 is inside the end 3a of the protective film 3 over the entire circumference, the above-described effect is exhibited over the entire circumference of the polarizing plate 1A.

  Moreover, since the polarizing plate 1A has a rectangular shape in plan view, it can be easily applied to various articles such as a liquid crystal display device.

<Second Embodiment>
The polarizing plate 1A may further include another optical function film. As other optical functional films, a reflective polarizer that transmits a certain kind of polarized light and reflects polarized light that exhibits the opposite property; a film with an antiglare function having a concavo-convex shape on the surface; a film with a surface antireflection function; Examples thereof include a reflective film having a reflective function on the surface; a transflective film having both a reflective function and a transmissive function; a viewing angle compensation film; and a retardation film. Below, the aspect provided with a reflection type polarizer is demonstrated.

  As shown in FIG. 3, the polarizing plate 1 </ b> B is a reflective polarizer on the surface of the polarizing plate comprising the polarizing film 2, the adhesive layer 4 and the protective film 3 on the polarizing film 2 side via the adhesive layer 5. 6 are stacked.

  The size and shape of the reflective polarizer 6 are the same as the size and shape of the protective film 3, and the end of the reflective polarizer 6 protrudes from the end of the polarizing film 2. Any reflective polarizer 6 can be used.

  The pressure-sensitive adhesive layer 5 can be composed of acrylic resin, silicone resin, polyester, polyurethane, polyether, or the like.

  The thickness of the pressure-sensitive adhesive layer 5 is preferably 2 to 50 μm, more preferably 2 to 40 μm, and still more preferably 2 to 30 μm.

  As a method of laminating the pressure-sensitive adhesive layer 5 on the polarizing film 2, for example, a method of applying a solution containing the above resin or any additive component to the polarizing film 2 may be applied. A method of transferring the film 5 to the polarizing film 2 after forming 5 may be used.

  The polarizing plate 1B is further provided with another pressure-sensitive adhesive layer (not shown) on the reflective polarizer 6 for the purpose of sticking to other articles, and a separator (not shown) is laminated thereon. May be.

  The separator is a peelable film that is attached for the purpose of protecting the pressure-sensitive adhesive layer or preventing the adhesion of foreign substances, and is peeled off when the polarizing plate 1B is used to expose the pressure-sensitive adhesive layer. The separator can be made of, for example, a polyethylene resin such as polyethylene, a polypropylene resin such as polypropylene, a polyester resin such as polyethylene terephthalate, and the like. Among these, a stretched film of polyethylene terephthalate is preferable.

  According to the polarizing plate 1B, the polarizing film 2 is prevented from being damaged or worn out. Further, the end portion 2 a of the polarizing film 2 is further protected by the end portion of the reflective polarizer 6 protruding beyond the end portion 2 a of the polarizing film 2.

  Note that the size and shape of the reflective polarizer 6 may be the same as the size and shape of the polarizing film 2 as in the polarizing plate 1C shown in FIG.

  Moreover, when the adhesive layer 5 is further provided on the protective film 3, as shown in FIG. 5, for example, the polarizing plate 1B is stuck on the back side (the lower side in the drawing) of the liquid crystal cell 8, and the other A polarizing plate 1A provided with a pressure-sensitive adhesive layer 5 on the surface of the polarizing film 2 is attached to the viewing side (the upper side in the figure) of the liquid crystal cell 8 to form a liquid crystal panel 9, and a backlight (surface light source device; The liquid crystal display device 10 can be manufactured by combining other members. In addition, although normally two polarizing plates are incorporated in the liquid crystal display device, the liquid crystal display device according to the present embodiment may include at least one polarizing plate.

  The preferred embodiment of the present invention has been described above, but the present invention is not limited to the above embodiment. For example, in the said embodiment, although the edge part 2a of the polarizing film 2 showed the aspect located inside the edge part 3a of the protective film 3 over the perimeter, the part located inside is the polarizing film 2 It does not have to extend over the entire circumference. In this case, the end 2 a of the polarizing film 2 is protected only at the portion located inside the end 3 a of the protective film 3.

  Moreover, in the said embodiment, although the mode that it was located inside by the same length over the perimeter of the polarizing film 2 was shown, you may change the grade of the dent of the polarizing film 2 by a place. For example, when a portion that is susceptible to impact during handling of the polarizing plate is known in advance, it is preferable to increase the recess width of the end of the polarizing film at that portion.

  Moreover, although the polarizing plate 1A, 1B showed the example which is planar view rectangle in the said embodiment, other squares, for example, a trapezoid, a parallelogram, a square, etc. may be sufficient, and it may be circular or elliptical. Also good. That is, the polarizing plates 1A and 1B can have any shape according to the shape of the article to which the polarizing plates 1A and 1B are attached.

  Moreover, although the adhesive layer 5 showed the aspect laminated | stacked on the polarizing film 2 side in 2nd Embodiment, the aspect which the adhesive layer 5 laminated | stacked also on the protective film 3 side, and other optical function layers were laminated | stacked It is good.

  Hereinafter, the contents of the present invention will be described more specifically with reference to examples and comparative examples. In addition, this invention is not limited to the following Example.

(1) Production of Polarizing Film A polyvinyl alcohol film having an average polymerization degree of about 2400 and a saponification degree of 99.9 mol% or more and a thickness of 20 μm was uniaxially stretched about 4 times in a dry process. The film was immersed in pure water at 40 ° C. for 1 minute while maintaining the stretched tension state, and then immersed in an aqueous solution having a weight ratio of iodine / potassium iodide / water of 0.1 / 5/100 at 28 ° C. for 60 seconds. . Thereafter, it was immersed in an aqueous solution having a weight ratio of potassium iodide / boric acid / water of 10.5 / 7.5 / 100 at 68 ° C. for 300 seconds. Subsequently, it was washed with pure water at 5 ° C. for 5 seconds and then dried at 70 ° C. for 180 seconds to obtain a polarizing film (polarizer) in which iodine was adsorbed and oriented on a uniaxially stretched polyvinyl alcohol film. The thickness of the polarizing film was 7 μm.

(2) Preparation of adhesive (2-1) Water-based adhesive Polyvinyl alcohol powder (trade name “KL-318” manufactured by Kuraray Co., Ltd., average polymerization degree 1800) was dissolved in hot water at 95 ° C., and the concentration was 3 wt. % Aqueous polyvinyl alcohol solution was prepared. The resulting aqueous solution was mixed with a crosslinking agent (trade name “Smilease Resin 650” manufactured by Taoka Chemical Co., Ltd.) at a ratio of 1 part by mass with respect to 2 parts by mass of the polyvinyl alcohol powder to obtain an aqueous adhesive.

(2-2) Cationic UV-curable adhesive The following components were mixed and defoamed to prepare an ultraviolet-curable adhesive. The photocationic polymerization initiator used was obtained in the form of a 50% propylene carbonate solution. The blending amount (2.25 parts by mass) shown below is the solid content.
3,4-epoxycyclohexylmethyl 3,4-epoxycyclohexanecarboxylate 75 mass parts 1,4-butanediol diglycidyl ether 20 mass parts 2-ethylhexyl glycidyl ether 5 mass parts triarylsulfonium hexafluoro Phosphate-based photocationic polymerization initiator ... 2.25 parts by mass

(2-3) Radical ultraviolet curable adhesive The following components were mixed and defoamed to prepare an ultraviolet curable adhesive.
・ Bis (3-ethyl-3-oxetanylmethyl) ether (Aron oxetane OXT-221, manufactured by Toagosei Co., Ltd.) 15 parts by mass ・ Tricyclodecane dimethanol diacrylate (A-DCP, manufactured by Shin-Nakamura Chemical Co., Ltd.) 50 mass parts 2-hydroxy-2-methyl-1-phenylpropan-1-one (DAROCUR 1173, manufactured by Ciba Specialty Chemicals) (photo radical polymerization initiator) ... 2.25 mass parts

(3) Production of single-sided protective polarizing plate (when using water-based adhesive)
A single-sided protective polarizing plate with a release film was prepared by the following procedure. A protective film was cut out in a size of 120 mm × 70 mm one by one from the roll of the polarizing film obtained in (1) above and a protective film (ZEONOR FILM ZEONOR FILM ZF14-023, thickness 23 μm, manufactured by Nippon Zeon Co., Ltd.). At this time, the polarizing film was adjusted to be slightly smaller than the protective film (the degree of “slightly” will be described later). The protective film is subjected to corona treatment, and a release film (trade name “KC8UX2MW”, TAC film manufactured by Konica Minolta Opto Co., Ltd., thickness 80 μm, no saponification treatment) is cut out separately, and the protective film, polarizing film The release film was laminated in this order.

  Then, while inject | pouring the water-system adhesive obtained by said (2-1) between a polarizing film and a protective film, inject | pour pure water between a polarizing film and a peeling film, and let it pass between bonding rolls. Thus, a laminated film comprising a protective film / aqueous adhesive layer / polarizing film / pure water / release film was obtained. Subsequently, the laminated film is heated in a drying apparatus at 80 ° C. for 300 seconds to dry the aqueous adhesive layer and volatilize and remove the pure water interposed between the polarizing film and the release film. A single-sided protective polarizing plate with a release film was obtained. The release film was peeled from the single-sided protective polarizing plate with a release film to obtain a single-sided protective polarizing plate.

(4) Production of single-sided protective polarizing plate (when UV curable adhesive is used)
A protective film was cut out one by one from the roll of the polarizing film obtained in (1) above and a protective film (Zeonor Film Zeonor Film ZF14-023, thickness 23 μm, manufactured by Nippon Zeon Co., Ltd.). At this time, it adjusted so that a polarizing film might become smaller than a protective film. The protective film was subjected to corona treatment, and a protective film and a polarizing film were laminated in this order.

  Next, the ultraviolet curable adhesive obtained in the above (2-2) or (2-3) is injected between the polarizing film and the protective film, and passed between the bonding rolls to protect the film / ultraviolet curable adhesive. It was set as the laminated film which consists of an agent / polarizing film. Subsequently, the UV curable adhesive was cured by performing UV irradiation from the protective film side using a UV irradiation apparatus to obtain a single-side protective polarizing plate.

(5) Production of single-sided protective polarizing plate with brightness-enhancing film Brightness-enhancing film (3M stock) via an acrylic pressure-sensitive adhesive on the polarizing film surface of the single-sided protective polarizing plate obtained in (3) and (4) above A company-made reflective polarizer (trade name “APF”) was bonded to obtain a single-side protective polarizing plate with a brightness enhancement film. At this time, the size of the brightness enhancement film was the same as that of the polarizing plate, and the brightness enhancement film was bonded in parallel with the stretching direction of the polarizing film.

(6) Preparation of polarizing plate with acrylic pressure-sensitive adhesive Acrylic pressure-sensitive adhesive with a separator film is bonded to the brightness-enhancing film surface of the single-sided protective polarizing plate with the brightness-improving film obtained in (5) above. A polarizing plate with an acrylic pressure-sensitive adhesive was obtained.

(7) Heat shock test A heat shock test was performed as an endurance test. A sample for a heat shock test was prepared by the following procedure.

  After sticking the sample obtained in (6) above to an alkali-free glass plate (“Eagle-XG” manufactured by Corning Co., Ltd.), the autoclave is subjected to pressure treatment for 20 minutes under conditions of a temperature of 50 ° C. and a pressure of 5 MPa. Subsequently, it was left for 1 day in an atmosphere at a temperature of 23 ° C. and a relative humidity of 60%. Then, using a thermal shock tester “TSA-301L-W” manufactured by Espec Co., Ltd., low temperature side −40 ° C. [holding time 30 minutes], normal temperature 23 ° C. [holding time 5 minutes], high temperature side 85 ° C. [holding time] 30 minutes], a durability test was performed in which the test tank was stored for 12 cycles under the conditions set so as to change. Then, the sample was taken out and the presence or absence of the crack-like appearance defect was confirmed.

(8) Examples and Comparative Examples Hereinafter, the results of carrying out “(7) heat shock test” for the polarizing plates produced according to the above-described procedures (1) to (6) will be shown.

[Example 1]
The size of the polarizing film is cut out so that the entire width in the vertical direction and the horizontal direction is 0.1 mm smaller than the size of the protective film, and the edge of the polarizing film is 0 with respect to the edge of the protective film on each side. A polarizing plate was prepared using a water-based adhesive, adjusted so as to be located on the inner side of 0.05 mm, and a heat shock test was performed. As a result, no cracks were observed in the polarizing film.

[Example 2]
The size of the polarizing film is cut out so that the entire width in the vertical direction and the horizontal direction is 0.1 mm smaller than the size of the protective film, and the edge of the polarizing film is 0 with respect to the edge of the protective film on each side. A polarizing plate was prepared using a cationic ultraviolet curable adhesive, adjusted so as to be located on the inner side of 0.05 mm, and a heat shock test was performed. As a result, no cracks were observed in the polarizing film.

[Example 3]
The size of the polarizing film is cut out so that the entire width in the vertical direction and the horizontal direction is 0.1 mm smaller than the size of the protective film, and the edge of the polarizing film is 0 with respect to the edge of the protective film on each side. A polarizing plate was prepared using a radical ultraviolet curable adhesive, adjusted so as to be located inside the .05 mm, and a heat shock test was performed. As a result, no cracks were observed in the polarizing film.

[Example 4]
A polarizing plate was produced in the same manner as in Example 1 except that triacetyl cellulose (manufactured by Konica Minolta Opto Co., Ltd., zero tack, thickness 20 μm) obtained by saponifying the protective film was used, and a heat shock test was performed. As a result, no cracks were observed in the polarizing film.

[Example 5]
A polarizing plate was produced in the same manner as in Example 2 except that triacetyl cellulose (manufactured by Konica Minolta Opto Co., Ltd., zero tack, thickness 20 μm) obtained by saponifying the protective film was used, and a heat shock test was performed. As a result, no cracks were observed in the polarizing film.

[Example 6]
A polarizing plate was produced in the same manner as in Example 3 except that triacetylcellulose (manufactured by Konica Minolta Opto Co., Ltd., zero tack, thickness 20 μm) obtained by saponifying the protective film was used, and a heat shock test was performed. As a result, no cracks were observed in the polarizing film.

[Comparative Example 1]
Cut out both polarizing film and protective film at 130mm x 80mm, and made polarizing plate using water-based adhesive, then cut each side by 5mm with super cutter, molded into 120mm x 70mm, and conducted heat shock test Carried out. As a result, a crack occurred at the end of the polarizing film.

[Comparative Example 2]
Both the polarizing film and the protective film are cut out at 130 mm × 80 mm, and after producing a polarizing plate using a cationic UV curable adhesive, each side is cut by 5 mm with a super cutter, and molded into 120 mm × 70 mm, A heat shock test was performed. As a result, as a result, a crack occurred at the end of the polarizing film.

[Comparative Example 3]
Both the polarizing film and the protective film are cut out at 130 mm × 80 mm, and after making a polarizing plate using a radical UV curable adhesive, each side is cut by 5 mm with a super cutter, and molded into 120 mm × 70 mm, A heat shock test was performed. As a result, many cracks occurred at the end of the polarizing film.

[Comparative Example 4]
The size of the polarizing film is cut out so that the entire width in the vertical direction and the horizontal direction are both 0.1 mm larger than the size of the protective film, and at each side, the end of the polarizing film is 0 with respect to the end of the protective film. A polarizing plate was prepared using a water-based adhesive, adjusted so that it was located outside by 0.05 mm, and a heat shock test was performed. As a result, a crack occurred at the end of the polarizing film.

[Comparative Example 5]
The size of the polarizing film is cut out so that the entire width in the vertical direction and the horizontal direction are both 0.1 mm larger than the size of the protective film, and at each side, the end of the polarizing film is 0 with respect to the end of the protective film. A polarizing plate was prepared using a cationic ultraviolet curable adhesive, adjusted so as to be located outside of 0.05 mm, and a heat shock test was performed. As a result, a crack occurred at the end of the polarizing film.

[Comparative Example 6]
The size of the polarizing film is cut out so that the entire width in the vertical direction and the horizontal direction are both 0.1 mm larger than the size of the protective film, and at each side, the end of the polarizing film is 0 with respect to the end of the protective film. A polarizing plate was prepared using a radical-type ultraviolet curable adhesive, adjusted to be located outside by 0.05 mm, and a heat shock test was performed. As a result, many cracks occurred at the end of the polarizing film.

  The present invention can be used, for example, as a component of a liquid crystal panel.

  DESCRIPTION OF SYMBOLS 1A, 1B, 1C ... Polarizing plate, 2 ... Polarizing film (polarizer), 2a ... End of polarizing film, 3 ... Protective film, 3a ... End of protective film, 4 ... Adhesive layer (adhesive), 5 DESCRIPTION OF SYMBOLS ... Adhesive layer, 6 ... Reflective polarizer (optical functional film), 8 ... Liquid crystal cell, 9 ... Liquid crystal panel, 10 ... Liquid crystal display device.

Claims (6)

Comprising a polarizer and a protective film laminated on only one side thereof with an adhesive,
The protective film is formed into a predetermined shape,
The protective film is laminated on the entire surface of one side of the polarizer,
A polarizing plate, wherein at least a part of the end of the polarizer is located 0.05 mm inside the end of the protective film.   The polarizing plate according to claim 1, wherein all end portions of the polarizer are located on an inner side than end portions of the protective film.   Laminated on at least one of the surface of the polarizer opposite to the side where the protective film is laminated and the surface of the protective film opposite to the side where the polarizer is laminated. The polarizing plate according to claim 1, further comprising an adhesive layer.   The polarizing plate of Claim 3 further provided with the optical function film laminated | stacked through the said adhesive layer.   The polarizing plate according to claim 4, wherein the optical functional film is a reflective polarizer.   A liquid crystal display provided with the polarizing plate as described in any one of Claims 1-5.

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